/*
 * Copyright (c) 2002 - 2006 IBM Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 */
package com.ibm.wala.examples.drivers;

import com.ibm.wala.classLoader.Language;
import com.ibm.wala.core.tests.callGraph.CallGraphTestUtil;
import com.ibm.wala.core.util.config.AnalysisScopeReader;
import com.ibm.wala.core.util.io.FileProvider;
import com.ibm.wala.core.viz.PDFViewUtil;
import com.ibm.wala.examples.properties.WalaExamplesProperties;
import com.ibm.wala.ipa.callgraph.AnalysisCacheImpl;
import com.ibm.wala.ipa.callgraph.AnalysisOptions;
import com.ibm.wala.ipa.callgraph.AnalysisScope;
import com.ibm.wala.ipa.callgraph.CGNode;
import com.ibm.wala.ipa.callgraph.CallGraph;
import com.ibm.wala.ipa.callgraph.CallGraphStats;
import com.ibm.wala.ipa.callgraph.Entrypoint;
import com.ibm.wala.ipa.callgraph.impl.Util;
import com.ibm.wala.ipa.callgraph.propagation.InstanceKey;
import com.ibm.wala.ipa.callgraph.propagation.LocalPointerKey;
import com.ibm.wala.ipa.cha.ClassHierarchy;
import com.ibm.wala.ipa.cha.ClassHierarchyFactory;
import com.ibm.wala.properties.WalaProperties;
import com.ibm.wala.types.ClassLoaderReference;
import com.ibm.wala.util.CancelException;
import com.ibm.wala.util.WalaException;
import com.ibm.wala.util.collections.HashSetFactory;
import com.ibm.wala.util.debug.Assertions;
import com.ibm.wala.util.graph.Graph;
import com.ibm.wala.util.io.CommandLine;
import com.ibm.wala.util.io.FileUtil;
import com.ibm.wala.util.viz.DotUtil;
import java.io.File;
import java.io.IOException;
import java.util.Collection;
import java.util.Iterator;
import java.util.Properties;
import java.util.function.Predicate;

/**
 * This simple example WALA application builds a call graph and fires off ghostview to visualize a
 * DOT representation.
 */
public class PDFCallGraph {
  public static boolean isDirectory(String appJar) {
    return new File(appJar).isDirectory();
  }

  public static String findJarFiles(String[] directories) {
    Collection<String> result = HashSetFactory.make();
    for (String directory : directories) {
      for (File f : FileUtil.listFiles(directory, ".*\\.jar", true)) {
        result.add(f.getAbsolutePath());
      }
    }
    return composeString(result);
  }

  private static String composeString(Collection<String> s) {
    StringBuilder result = new StringBuilder();
    Iterator<String> it = s.iterator();
    for (int i = 0; i < s.size() - 1; i++) {
      result.append(it.next());
      result.append(File.pathSeparator);
    }
    if (it.hasNext()) {
      result.append(it.next());
    }
    return result.toString();
  }

  private static final String PDF_FILE = "cg.pdf";

  /**
   * Usage: args = "-appJar [jar file name] {-exclusionFile [exclusionFileName]}" The "jar file
   * name" should be something like "c:/temp/testdata/java_cup.jar"
   */
  public static void main(String[] args) throws IllegalArgumentException, CancelException {
    run(args);
  }

  /**
   * Usage: args = "-appJar [jar file name] {-exclusionFile [exclusionFileName]}" The "jar file
   * name" should be something like "c:/temp/testdata/java_cup.jar"
   */
  public static Process run(String[] args) throws IllegalArgumentException, CancelException {
    Properties p = CommandLine.parse(args);
    validateCommandLine(p);
    return run(
        p.getProperty("appJar"),
        p.getProperty("exclusionFile", CallGraphTestUtil.REGRESSION_EXCLUSIONS));
  }

  /**
   * @param appJar something like "c:/temp/testdata/java_cup.jar"
   */
  public static Process run(String appJar, String exclusionFile)
      throws IllegalArgumentException, CancelException {
    try {
      Graph<CGNode> g = buildPrunedCallGraph(appJar, new FileProvider().getFile(exclusionFile));

      Properties p = null;
      try {
        p = WalaExamplesProperties.loadProperties();
        p.putAll(WalaProperties.loadProperties());
      } catch (WalaException e) {
        e.printStackTrace();
        Assertions.UNREACHABLE();
      }
      String pdfFile = p.getProperty(WalaProperties.OUTPUT_DIR) + File.separatorChar + PDF_FILE;

      String dotExe = p.getProperty(WalaExamplesProperties.DOT_EXE);
      DotUtil.dotify(g, null, PDFTypeHierarchy.DOT_FILE, pdfFile, dotExe);

      String gvExe = p.getProperty(WalaExamplesProperties.PDFVIEW_EXE);
      return PDFViewUtil.launchPDFView(pdfFile, gvExe);

    } catch (WalaException | IOException e) {
      e.printStackTrace();
      return null;
    }
  }

  /**
   * @param appJar something like "c:/temp/testdata/java_cup.jar"
   * @return a call graph
   */
  public static Graph<CGNode> buildPrunedCallGraph(String appJar, File exclusionFile)
      throws WalaException, IllegalArgumentException, CancelException, IOException {
    AnalysisScope scope =
        AnalysisScopeReader.instance.makeJavaBinaryAnalysisScope(
            appJar,
            exclusionFile != null
                ? exclusionFile
                : new File(CallGraphTestUtil.REGRESSION_EXCLUSIONS));

    ClassHierarchy cha = ClassHierarchyFactory.make(scope);

    Iterable<Entrypoint> entrypoints =
        com.ibm.wala.ipa.callgraph.impl.Util.makeMainEntrypoints(cha);
    AnalysisOptions options = new AnalysisOptions(scope, entrypoints);

    // //
    // build the call graph
    // //
    com.ibm.wala.ipa.callgraph.CallGraphBuilder<InstanceKey> builder =
        Util.makeZeroCFABuilder(Language.JAVA, options, new AnalysisCacheImpl(), cha);
    CallGraph cg = builder.makeCallGraph(options, null);

    System.err.println(CallGraphStats.getStats(cg));

    return pruneForAppLoader(cg);
  }

  public static Graph<CGNode> pruneForAppLoader(CallGraph g) {
    return PDFTypeHierarchy.pruneGraph(g, new ApplicationLoaderFilter());
  }

  /**
   * Validate that the command-line arguments obey the expected usage.
   *
   * <p>Usage:
   *
   * <ul>
   *   <li>args[0] : "-appJar"
   *   <li>args[1] : something like "c:/temp/testdata/java_cup.jar"
   * </ul>
   *
   * @throws UnsupportedOperationException if command-line is malformed.
   */
  public static void validateCommandLine(Properties p) {
    if (p.get("appJar") == null) {
      throw new UnsupportedOperationException("expected command-line to include -appJar");
    }
  }

  /**
   * A filter that accepts WALA objects that "belong" to the application loader.
   *
   * <p>Currently supported WALA types include
   *
   * <ul>
   *   <li>{@link CGNode}
   *   <li>{@link LocalPointerKey}
   * </ul>
   */
  private static class ApplicationLoaderFilter implements Predicate<CGNode> {

    @Override
    public boolean test(CGNode o) {
      if (o == null) return false;
      return o.getMethod()
          .getDeclaringClass()
          .getClassLoader()
          .getReference()
          .equals(ClassLoaderReference.Application);
    }
  }
}
